Dynamic non-linear display

ABSTRACT

A method and apparatus is disclosed for displaying a dynamic parameter, the apparatus comprises a display unit receiving a display signal and displaying a scale that changes dynamically and non-linearly in accordance with a selected display algorithm, the display unit further displaying a pointer pointing to said scale in accordance with a reading of said dynamic parameter, thereby emphasizing a range of said reading of said dynamic parameter.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation-in-part of U.S. patentapplication Ser. No. 10/670,780 filed on Sep. 26, 2003 now U.S. Pat. No.7,062,364 which claims priority from U.S. provisional patent applicationNo. 60/415,807, entitled “Electronic non-linear aircraft altitude andvertical speed display”, filed on Oct. 4, 2002, the specifications ofwhich are hereby incorporated by reference.

TECHNICAL FIELD

This invention relates to the field of instruments. More precisely, thisinvention relates to dynamic non-linear displays.

BACKGROUND OF THE INVENTION

Measurement and displaying of dynamic parameters of an aircraft is a keyissue for properly controlling, managing and validating aircraftposition and velocity.

It is known that measurement of aircraft altitude and vertical speed, bybarometric and other means, is a mature technology which is founded onprinciples which have remained relatively unchanged since the firstdeployment of altimeters and vertical speed indicators (VSI).

In contrast, the “modern” altimeter display has evolved through fourdistinct iterations.

An earliest modern variant, the “three-pointer” consists of a circularanalog display housing three concentric pointers read against a commonscale. A pointer is dedicated for displaying each of the 100's, 1,000sand 10,000s feet as shown in FIG. 1 a. This format is difficult tointerpret, particularly during dynamic situations. Use of thistechnology resulted in several aircraft accidents because the small10,000 ft pointer is easily obscured by larger pointers, leading tointerpretation errors of multiples of 10,000 ft. This tendency becameunacceptable with the advent of jet aircraft, whose high rates of climband descent rendered the three-pointer altimeter virtually useless. Itwill be appreciated by someone skilled in the art that the three-pointeraltimeter is still in widespread use in low-performance general aviationaircraft.

A second generation of mechanical altimeters, the “counter-pointer”altimeter, is a refinement of the “three-pointer” altimeter whichcomprises a single 100 ft pointer, sweeping over a circular scale, withan additional digital display of altitude presented on a drum or counteron the face of the instrument as shown in FIG. 1 b.

Although the details of the digital display, such as its smallestdigital altitude increment, vary between different embodiments, theprinciple remains unaltered. The main benefits of the “counter-pointer”altimeter include its ease of interpretation and elimination of the10,000 ft interpretation error potential.

A third generation of altimeters comprises a moving vertical altitudetape read against a central stationary pointer, as shown in FIG. 2. Theinstrument typically includes a digital readout of the aircraft altitudeadjacent to the tape display. Refinements to this system includeprovision of a vertical speed display adjacent to the altitude scale,and which allows the pilot to monitor altitude and vertical speedsimultaneously, with a minimum of eye movement.

A current generation of altimeters reflects a transition from mechanicalinstruments to Electronic Flight Instrument Systems (EFIS) and Head-upDisplays (HUD). Such systems have allowed the altitude displayindications to be decoupled from any “physical” altimeter instrument,thereby allowing incorporation of new display formats.

Modern altimeter formats described above have several importantdisadvantages.

Except at very low altitudes, there is no analog representation of theaircraft's altitude above the altitude reference datum which istypically mean sea-level (MSL). This is because at high altitudes,neither the counter pointer nor the tape altimeter can show thezero-altitude datum, because of the scaling compromise between adequateresolution and adequate range. In other words, the analog part of thesealtimeters can only display a relatively narrow altitude band around theaircraft's current altitude, which typically does not include the zeropoint. This is an important drawback, because it has been contemplatedthat humans are much better at evaluating rates of change of analog data(e.g. pointers) than digital data, and the simultaneous display of thezero datum and the reference datum is critical, particularly in verydynamic situations. Traditional implementations have been unable todisplay the altitude information in the preferred analog fashion, whilesimultaneously displaying both the zero datum and current altitude.

Furthermore, the resolution of the mechanical altimeters is generallyfixed at all altitudes, even though flight operations may requirediffering resolutions for different circumstances (e.g. higherresolution is desirable at low altitudes, where terrain clearance ismost critical).

With respect to aircraft airspeed, it is known that measurement of theaircraft airspeed, by pilot-static means, is also known as a very maturetechnology which is founded on principles which have remained largelyunchanged since the deployment of the first airspeed indicators (ASI).Modern airspeed indicators takes one of two forms: a dial/pointerdisplay, occasionally supplemented with a digital counter and the fixedpointer/moving tape display typically incorporated in Electronic FlightInstrument Systems (EFIS) and Head-Up Display (HUD), as shown in FIG. 3.Both of these formats share an important disadvantage, they use a fixedscale which requires a tradeoff between resolution and scale range. Inother words, a large scale is more legible, but has a relatively smalldisplay range, whereas a smaller scale achieves good range whilecompromising legibility.

The problems highlighted herein may also be present outside the contextof an aircraft.

There is therefore a need for a method and apparatus that will overcomethe above-identified drawbacks.

SUMMARY OF THE INVENTION

It is an object of the invention to provide an apparatus for displayinga dynamic parameter using a flexible dynamic parameter scale.

It is another object of the invention to provide a method for displayinga dynamic parameter using a flexible dynamic parameter scale.

According to a first aspect of the invention there is provided anapparatus for displaying a dynamic parameter, the apparatus comprising aprocessing unit receiving a selected display algorithm signal and areading of the dynamic parameter, the processing unit determining adisplay signal; and a display unit receiving the display signal anddisplaying a scale having scale ends, the scale changing dynamically andnon-linearly in accordance with the selected display algorithm togetherwith a minimum dynamic parameter value and a maximum dynamic parametervalue, the display unit further displaying a pointer pointing to thescale in accordance with the reading of the dynamic parameter, such thatthe selected display algorithm constantly and exactly fits the reading,and the minimum and maximum dynamic parameter values to the scale,thereby emphasizing a range of the reading of the dynamic parameterwhile keeping the minimum and the maximum dynamic parameter valuesconstantly and in view at respective scale ends.

According to another aspect of the invention there is provided a methodfor displaying a dynamic parameter, the method comprising providing areading of the dynamic parameter, generating a scale having scale ends,the scale changing dynamically and non-linearly using the providedreading of the dynamic parameter and a selected display algorithm signaltogether with a minimum dynamic parameter value and a maximum dynamicparameter value, and a pointer pointing to the scale in accordance withthe reading of the dynamic parameter and displaying the scale, theminimum dynamic parameter value and the maximum dynamic parameter value,such that the selected display algorithm constantly and exactly fits thereading, and the minimum and maximum dynamic parameter values to thescale, thereby emphasizing a range of the reading of the dynamicparameter while keeping the minimum and the maximum dynamic parametervalues constant and in view at respective scale ends.

According to another aspect of the invention, there is provided anapparatus for displaying a dynamic parameter, the apparatus comprising adisplay unit receiving a display signal and displaying a scale thatchanges dynamically and non-linearly in accordance with a selecteddisplay algorithm, the display unit further displaying a pointerpointing to the scale in accordance with a reading of the dynamicparameter, thereby emphasizing a range of the reading of the dynamicparameter.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the present invention will becomeapparent from the following derailed description, taken in combinationwith the appended drawings, in which:

FIG. 1 a is a front view of a “three-pointer” prior art altimeter; itwill be appreciated that efforts are required to synthesize the readingsof the three pointers into a coherent altitude; furthermore it will beappreciated that the small 10,000 ft pointer may be occluded by a largerone;

FIG. 1 b is a front view of a “counter pointer” prior art altimeter;

FIG. 2 is a front view of a prior art embodiment of a tape altimeter;someone skilled in the art will appreciate the absence of a zero, meansea level or ground plane reference datum due to the small portion ofthe hypothetical “tape” which is visible due to scale constraints;

FIG. 3 is a front view of a fixed pointer/moving tape prior art displaytypically incorporated in Electronic Flight Instrument Systems (EFIS)and Head-Up Display (HUD);

FIG. 4 is a block diagram of an electronic non-linear aircraft dynamicparameter display comprising a processing unit and a display unit inaccordance with a preferred embodiment of the invention;

FIG. 5 is a flowchart which shows how the electronic non-linear aircraftdynamic parameter display operates in the preferred embodiment of theinvention;

FIG. 6 is a diagram which shows a first example of a dynamic parametertape provided on an electronic non-linear aircraft dynamic parameterdisplay;

FIG. 7 is a diagram which shows a second example of the dynamicparameter tape provided on the electronic non-linear aircraft dynamicparameter display;

FIG. 8 is a diagram which shows a third example of the dynamic parametertape provided on the electronic non-linear aircraft dynamic parameterdisplay;

FIG. 9 is a block diagram which shows a first embodiment of theelectronic non-linear aircraft dynamic parameter display where thedynamic parameter is altitude;

FIG. 10 is a flowchart which shows how the electronic non-linearaircraft dynamic parameter display operates in the first embodiment ofthe invention where the dynamic parameter is altitude;

FIG. 11 is a picture which shows a first example of the electronicnon-linear aircraft dynamic parameter display in the first embodiment ofthe invention where the dynamic parameter is altitude;

FIG. 12 is a picture which shows a second example of the electronicnon-linear aircraft dynamic parameter display in the first embodiment ofthe invention where the dynamic parameter is altitude;

FIG. 13 is a block diagram which shows a second embodiment of theelectronic non-linear aircraft dynamic parameter display where thedynamic parameter is speed;

FIG. 14 is a flowchart which shows how the electronic non-linearaircraft dynamic parameter display operates in the second embodiment ofthe invention where the dynamic parameter is speed; and

FIG. 15 is a picture which shows an example of the electronic non-linearaircraft dynamic parameter display in the second embodiment of theinvention where the dynamic parameter is speed.

It will be noted that throughout the appended drawings, like featuresare identified by like reference numerals.

DETAILED DESCRIPTION OF THE INVENTION

It will be appreciated that the method and apparatus for displaying adynamic parameter using a flexible dynamic parameter scale may be usedin displays of any moving vessel, an example of which is aircraft. Otherexamples include cars, motorcycles, buses, ships, trains, etc.Alternatively, the method and apparatus for displaying a dynamicparameter using a flexible dynamic parameter scale may be used todisplay and monitor data originating from any data generating unit suchas industrial machines, sensor units or the like.

Now referring to FIG. 4, there is shown a preferred embodiment of anelectronic non-linear aircraft dynamic parameter display 5.

The electronic non-linear aircraft dynamic parameter display 5 comprisesa processing unit 8 and a display unit 10. In a preferred embodiment ofthe invention, the processing unit 8 is a digital computer ormicroprocessor, while the display unit 10 is either an Electronic FlightInstrument System (EFIS), a Multifunction Display (MFD), or a Head-UpDisplay (HUD), all of which are well known to someone versed in the art.

The processing unit 8 receives a selected display algorithm signalprovided by a user interface 6 and a measured dynamic parameter signalprovided by a dynamic parameter measuring device 12.

The processing unit 8 provides a dynamic parameter display signal to thedisplay unit 10.

Now referring to FIG. 5, there is shown how the electronic non-linearaircraft dynamic parameter display 5 operates in a preferred embodimentof the invention.

According to step 20, a display algorithm is selected using the userinterface 6. The selected display algorithm signal is provided by theuser interface 6 to the processing unit 8. In one embodiment, thedisplay algorithm is selected by a pilot of the aircraft while inanother embodiment of the invention, the display algorithm is selectedby the air-data or display computer, or the like. For simpleembodiments, the display algorithm may be a fixed algorithm which is notuser-selectable.

According to step 22, a dynamic parameter signal is measured using thedynamic parameter measuring device 12 which provides the measureddynamic parameter signal to the processing unit 8.

According to step 24, the dynamic parameter display signal, comprisingdata for displaying a dynamic parameter tape on the display unit 10.Prior to displaying the dynamic parameter tape, the processing unit 8first determines the dynamic parameter display signal using the measureddynamic parameter signal and the selected display algorithm signal andprovides the created dynamic parameter display signal to the displayunit 10.

Now referring to FIG. 6, there is shown a first example of a dynamicparameter tape 30 provided on an electronic non-linear aircraft dynamicparameter display 10.

The dynamic parameter tape 30 comprises a dynamic non-linear dynamicparameter scale 34, a corresponding non-linear dynamic parameter valuescale 32 and a pointer 36.

By convention, the dynamic non-linear dynamic parameter scale 34 and thecorresponding non-linear dynamic parameter value scale 32 are displayedvertically. In alternative embodiments, the dynamic non-linear dynamicparameter scale 34 and the corresponding non-linear dynamic parametervalue scale 32 may be displayed horizontally or at any other angles.

The dynamic non-linear dynamic parameter scale 34 is a dynamic parameterscale that is provided between a first dynamic parameter scale end 38and a second dynamic parameter scale end 40.

The corresponding non-linear dynamic parameter value scale 32 comprisesa plurality of corresponding dynamic parameter values and is providedbetween a first dynamic parameter value 42 corresponding to the firstdynamic parameter scale end 38 and a second dynamic parameter value 44corresponding to the second dynamic parameter scale end 40.

The pointer 36 is located substantially at an equal distance between end38 and end 40 of the dynamic non-linear dynamic parameter scale 34. Thepointer 36 comprises an indication of the measured dynamic parametersignal.

It will be appreciated that the dynamic non-linear dynamic parameterscale 34 is adapted according to the selected display algorithm signal.As explained below, in one embodiment, the selected display algorithmsignal is an exponential factor while in another embodiment of theinvention, the selected display algorithm signal is a logarithmicfactor. Alternatively, the selected display algorithm signal is ageometric factor.

Furthermore, it will be appreciated that while a first part of thedynamic non-linear dynamic parameter scale 34, for example, the partabove pointer 36, is adapted according to a first selected displayalgorithm signal, a second part of the dynamic non-linear dynamicparameter scale 34, for example, the part below pointer 36, may beadapted according to a second selected display algorithm signal.

In one embodiment, the first dynamic parameter value 42 corresponding tothe first dynamic parameter scale end 38 and the second dynamicparameter value 44 corresponding to the second dynamic parameter scaleend 40 are provided by the user interface 6 while in another embodiment,the first dynamic parameter value 42 and the second dynamic parametervalue 44 are automatically selected.

Now referring to FIG. 7, there is shown a second example of a dynamicparameter tape 50 provided on an electronic non-linear aircraft dynamicparameter display.

The dynamic parameter tape 50 comprises a dynamic non-linear dynamicparameter scale 52, a corresponding non-linear dynamic parameter valuescale 54, a pointer 56 and an adjacent vertical bar 66.

By convention, the dynamic non-linear dynamic parameter scale 52 and thecorresponding non-linear dynamic parameter value scale 54 are displayedvertically. In an alternative embodiment, the dynamic non-linear dynamicparameter scale 52 and the corresponding non-linear dynamic parametervalue scale 54 may be displayed horizontally.

The dynamic non-linear dynamic parameter scale 52 comprises a dynamicparameter scale that is provided between a first dynamic parameter scaleend 58 and a second dynamic parameter scale end 60.

The corresponding non-linear dynamic parameter value scale 54 comprisesa plurality of corresponding dynamic parameter values and is providedbetween a first dynamic parameter value 62 corresponding to the firstdynamic parameter scale end 56 and a second dynamic parameter value 64corresponding to the second dynamic parameter scale end 60.

The pointer 56 is located substantially at an equal distance between end58 and end 60 of the dynamic non-linear dynamic parameter scale 52. Thepointer 56 comprises an indication of the measured dynamic parametersignal.

The adjacent vertical bar 66 is located adjacent on the correspondingnon-linear dynamic parameter value scale 54. Alternatively, the adjacentvertical bar 66 is located adjacent on the dynamic non-linear dynamicparameter scale 52.

The adjacent vertical bar 66 comprises a variable end 68 which isadjacent to a corresponding future dynamic parameter value 53. Theadjacent vertical bar 66 therefore provides an indication of a futuredynamic parameter value if a current variation of the dynamic parameteris maintained during a predetermined amount of time.

The skilled addressee will appreciate that the corresponding futuredynamic parameter value 53 can easily be seen by a pilot of the aircraftlooking at the variable end 68.

It will be appreciated that the dynamic non-linear dynamic parameterscale 52 is adapted according to the selected display algorithm signal.As explained below, in one embodiment, the selected display algorithmsignal is an exponential factor while in another embodiment of theinvention, the selected display algorithm signal is a logarithmicfactor. Alternatively, the selected display algorithm signal is ageometric factor.

Furthermore, it will be appreciated that while a first part of thedynamic non-linear dynamic parameter scale 52, for example, the partabove pointer 56, is adapted according to a first selected displayalgorithm signal, a second part of the dynamic non-linear dynamicparameter scale 52, for example, the part below pointer 56, may beadapted according to a second selected display algorithm signal.

In one embodiment, the first dynamic parameter value 62 corresponding tothe first dynamic parameter scale end 58 and the second dynamicparameter value 64 corresponding to the second dynamic parameter scaleend 60 are provided by the user interface 6 while in another embodiment,the first dynamic parameter value 62 and the second dynamic parametervalue 64 are automatically selected. In fact it will be appreciated thatthe dynamic non-linear dynamic parameter scale 52 expands from the firstdynamic parameter value 62 and the second dynamic parameter value 64toward the pointer 56.

Now referring to FIG. 8, there is shown a third example of a dynamicparameter tape 80 provided on an electronic non-linear aircraft dynamicparameter display.

The dynamic parameter tape 80 comprises a dynamic non-linear dynamicparameter scale 82, a corresponding non-linear dynamic parameter valuescale 84, a pointer 86, an adjacent vertical bar 96 and an indication ofa dynamic parameter variation with respect to a predetermined amount oftime 100.

By convention, the dynamic non-linear dynamic parameter scale 82 and thecorresponding non-linear dynamic parameter value scale 84 are displayedvertically. In an alternative embodiment, the dynamic non-linear dynamicparameter scale 82 and the corresponding non-linear dynamic parametervalue scale 84 are displayed horizontally.

The dynamic non-linear dynamic parameter scale 82 comprises a dynamicparameter scale that is provided between a first dynamic parameter scaleend 88 and a second dynamic parameter scale end 90.

The corresponding non-linear dynamic parameter value scale 84 comprisesa plurality of corresponding dynamic parameter values and is providedbetween a first dynamic parameter value 92 corresponding to the firstdynamic parameter scale end 88 and a second dynamic parameter value 93corresponding to the second dynamic parameter scale end 90.

The pointer 86 is located substantially in the middle of the dynamicnon-linear dynamic parameter scale 82. The pointer 86 comprises anindication of the measured dynamic parameter signal.

The adjacent vertical bar 96 is located adjacent on the correspondingnon-linear dynamic parameter value scale 84. Alternatively, the adjacentvertical bar 96 is located adjacent on the dynamic non-linear dynamicparameter scale 82.

The adjacent vertical bar 96 comprises a variable end 98 which isadjacent to a corresponding future dynamic parameter value 101. Theadjacent vertical bar 96 therefore provides an indication of a futuredynamic parameter value if a current variation of the dynamic parameteris maintained during a predetermined amount of time. The adjacentvertical bar 96 further comprises the indication of a dynamic parametervariation with respect to a predetermined amount of time 100

The skilled addressee will appreciate that the corresponding futuredynamic parameter value 101 can easily be seen by a pilot of theaircraft looking at the variable end 98.

It will be appreciated that the dynamic non-linear dynamic parameterscale 82 is adapted according to the selected display algorithm signal.As explained below, in one embodiment, the selected display algorithmsignal is an exponential factor while in another embodiment of theinvention, the selected display algorithm signal is a logarithmicfactor. Alternatively, the selected display algorithm signal is ageometric factor.

Furthermore, it will be appreciated that while a first part of thedynamic non-linear dynamic parameter scale 82 is adapted according to afirst selected display algorithm signal, a second part of the dynamicnon-linear dynamic parameter scale 82 may be adapted according to asecond selected display algorithm signal.

Now referring to FIG. 9, there is shown a block diagram which shows afirst embodiment of the invention where the electronic non-linearaircraft dynamic parameter display is an electronic non-linear aircraftaltimeter display 118.

The electronic non-linear aircraft altimeter display 118 comprises aprocessing unit 112 and a display unit 114.

Still in this first embodiment of the invention, the processing unit 112is an air data computer, which is well known to someone versed in theart, while the display unit 114 is either an Electronic FlightInstrument System (EFIS), a Multifunction Display (MFD), or a Head-UpDisplay (HUD), all of which are well known to someone versed in the art.

The processing unit 112 receives a selected display algorithm signal andan altitude reference signal provided by the user interface 110 and ameasured altitude signal provided by the altitude measuring device 116.

The processing unit 112 provides an altitude display signal to thedisplay unit 114.

Now referring to FIG. 10, there is shown how the electronic non-linearaircraft altimeter display 118 operates in the preferred embodiment ofthe invention.

According to step 120, a display algorithm is selected using the userinterface 110. The selected display algorithm signal is provided by theuser interface 110 to the processing unit 112. In one embodiment, thedisplay algorithm is selected by a pilot of the aircraft while inanother embodiment of the invention, the display algorithm is selectedby the air data or display computer, or the like. For simpleembodiments, the display algorithm may be a fixed algorithm which is notuser-selectable.

According to step 122, an altitude reference signal is selected usingthe user interface 110. The selected altitude reference signal isprovided by the user interface 110 to the processing unit 112. In oneembodiment, the altitude reference signal is selected by a pilot of theaircraft while in the preferred embodiment of the invention, thealtitude reference signal is provided by the air data computer or thelike. The altitude reference signal typically represents a datumaltimeter setting expressed in millibars, inches of Mercury, or as analtitude value in feet or meters.

According to step 124, an altitude signal is measured using the altitudemeasuring device 116 which provides the measured altitude signal to theprocessing unit 112.

According to step 126, the altitude display signal, comprising analtitude tape is provided on the display unit 114. The altitude tape isprovided by first determining the altitude display signal using themeasured altitude signal, the selected altitude reference signal and theselected display algorithm signal and providing the created altitudedisplay signal to the display unit 114.

Now referring to FIG. 11, there is shown a first example of an altitudetape 130 provided on an electronic non-linear aircraft altitude display.

The altitude tape 130 comprises a dynamic non-linear altitude scale 134,a corresponding non-linear altitude value scale 132, a pointer 144, anadjacent vertical bar 146 and an indication of an altitude variationwith respect to a predetermined amount of time 150.

By convention, the dynamic non-linear altitude scale 134 and thecorresponding non-linear altitude value scale 132 are displayedvertically. In an alternative embodiment, the dynamic non-linearaltitude scale 134 and the corresponding non-linear altitude value scale132 may be displayed horizontally.

The dynamic non-linear altitude scale 134 comprises an altitude scalethat is provided between a first altitude scale end 136 and a secondaltitude scale end 138.

The corresponding non-linear altitude value scale 132 comprises aplurality of corresponding altitude values and is provided between afirst altitude value 140 corresponding to the first altitude scale end136 and a second altitude value 142 corresponding to the second altitudescale end 138.

The pointer 144 is located substantially in the middle of the dynamicnon-linear altitude scale 134. The pointer 144 comprises an indicationof the measured altitude signal. In this example, the measured altitudesignal is 5000 ft.

The adjacent vertical bar 146 is located adjacent on the correspondingnon-linear altitude value scale 132. Alternatively, the adjacentvertical bar 146 is located adjacent on the dynamic non-linear altitudescale 134.

The adjacent vertical bar 146 comprises a variable end 148 which isadjacent to a corresponding future altitude value 152. The adjacentvertical bar 146 is expandable between the measured altitude signal andthe variable end 148. The adjacent vertical bar 146 therefore providesan indication of a future altitude value if a current variation of thealtitude is maintained during a predetermined amount of time. Theadjacent vertical bar 146 further comprises the indication of analtitude variation with respect to a predetermined amount of time 150.

In the preferred embodiment, the predetermined amount of time is 1 min.In this example, the indication of an altitude variation with respect toa predetermined amount of time 150 is 1000 ft/min. Still in thisexample, the corresponding future altitude value 152 is 6000 ft.

The skilled addressee will appreciate that the corresponding futurealtitude value 152 can easily be seen by a pilot of the aircraft lookingat the variable end 148.

It will be appreciated that the dynamic non-linear altitude scale 134 isadapted according to the selected display algorithm signal.

In fact, the dynamic non-linear altitude scale 134 is constantly adaptedaccording to various principles detailed below.

A first principle is the fact that the dynamic non-linear altitude scale134 is substantially centered on the measured altitude signal. It willbe appreciated by someone skilled in the art that this first principleenables a proper presentation of altitude information to the pilot ofthe aircraft.

A second principle is the fact that, preferably, the first altitudevalue 140 represents the altimeter setting datum. The altimeter settingdatum may be the mean sea level in one embodiment. In anotherembodiment, the altimeter setting datum may be a standard pressure datum(29.92 inch of mercury). In another embodiment, the altimeter datum maybe the surface itself in the case where the altitude measuring device118 is a radar altimeter or radio altimetry device. The altimetersetting datum may be manually set or obtained from the air data computeror radar altimeter.

A third principle relates to the fact that the dynamic non-linearaltitude scale 134 is scaled using the selected display algorithm signalin order to fit both the measured altitude signal and the altimetersetting datum 140 in the available display space.

In one embodiment, the selected display algorithm signal is anexponential factor. In another embodiment of the invention, the selecteddisplay algorithm signal is a logarithmic factor. In another alternativeembodiment, the selected display algorithm signal is a geometric factor.In a preferred embodiment, the selected display algorithm signal is setso that the scale of the dynamic non-linear altitude scale 134 decreasesas it diverges from a current altitude; i.e., the highest resolution inthe dynamic non-linear altitude scale 134 is observed immediatelyadjacent to the measured altitude signal of the aircraft.

The choice of a geometric factor, a logarithmic factor, an exponentialfactor or any other non-linear selected display algorithm signal maydepend on a desired application and a desired altitude display range.

A fourth principles relates to the fact that above the measured altitudesignal, the dynamic non-linear altitude scale 134 is scaled by a similargeometric factor, logarithmic factor, exponential factor or any othernon-linear selected display algorithm signal to the second altitudevalue 142. Because of the relative greater significance of altitudesbelow the aircraft, it is possible to adapt an upper scaling factor toshow a smaller altitude scale above the measured altitude signal thanbelow the measured altitude signal. It will be appreciated that as perthe third principle, the selected display algorithm signal may also bechanged automatically.

Someone skilled in the art will appreciate that the high resolution islocated where it is most important to maintain an accurate altitude inorder to comply, for instance, with air traffic controller (ATC)clearances; and simultaneously, a clear graphic indication of theaircraft's relationship to the first altitude value 140 is given.

As mentioned previously, it will be appreciated that while a first partof the dynamic non-linear altitude scale 134, for instance, the partabove the pointer 144, is adapted according to a first selected displayalgorithm signal, a second part of the dynamic non-linear altitude scale134, for instance, the part below the pointer 144 may be adaptedaccording to a second selected display algorithm signal.

Now referring to FIG. 12, there is shown a second example of thealtitude tape 130 provided on an electronic non-linear aircraft altitudedisplay.

In this example, the pointer 144 displays a measured altitude signal of5000 ft.

Still in this example, the indication of an altitude variation withrespect to a predetermined amount of time 150 is −3000 ft/min and thecorresponding future altitude value 152 will be 2000 ft if the aircraftmaintains its rate of descent.

It will further be appreciated that the dynamic non-linear altitudescale 134 is constantly adapted according to the display algorithmsignal in order to emphasize a range of altitude; such constantadaptation enables the pilot of the aircraft to have a good appreciationof the dynamics of the aircraft; more precisely, the skilled addresseewill appreciate that in the case of a descent, the dynamic non-linearspeed scale 134 increases as there is less altitude in order to “fit”into the available display area. This results in increasing resolutionwhere it is most necessary which is at low altitudes.

As a corollary, for a given rate of climb or descent, the dynamicnon-linear speed scale 134 will move more rapidly at low altitudes thanat high altitudes, because the scale factor is greater in the formercase. This has a beneficial effect of highlighting high descent rates atlow altitudes by giving them greater saliency.

While it may be argued that the adjacent vertical bar is analogous toexisting vertical speed indicator (VSI), it will be appreciated thatprior art vertical speed indicators are incapable of showing very highrates of change while maintaining adequate resolution for normaloperations. Accordingly, it is not unusual for contemporary verticalspeed indicators to be “pegged” particularly during high-speed descents,so the pilot has little idea of the actual descent rate and itsrelationship with current altitude, particularly for high performanceaircraft. This is unfortunately also the case with prior art verticalspeed indicator displays which incorporate digital readouts, because thedetermination of “time-to-impact” still requires a mental division ofthe measured altitude signal (which is changing very rapidly) by theinstantaneous vertical speed indicator reading.

The mental division is usually an impossible task under dynamicconditions with a high workload.

The skilled addressee will appreciate that such shortcoming is notpossible with the present invention since the only time when verticalspeed indicator will be “pegged” will be when ground impact is in lessthan 1 min.

In such case, the imminent impact will be obvious, and the digitalreadout 150 will still provide the required rate information to thepilot.

It will further be appreciated that a further benefit of such embodimentof the altitude tape 130 is that the pilot may easily achieve the idealasymptotic level-off at a desired altitude simply by adjusting the rateof climb or descent to anchor the variable end 58 to the desiredlevel-off altitude. Used in this manner, the constant adaptation of thedynamic non-linear altitude scale 134 has the effect of graduallyreducing the rate of climb or descent to zero as the difference betweenthe required and current measured altitude signal diminishes.

Now referring to FIG. 13, there is shown a block diagram which shows asecond embodiment of the invention where the electronic non-linearaircraft dynamic parameter display is an electronic non-linear aircraftspeed display 162.

The electronic non-linear aircraft speed display 162 comprises aprocessing unit 164 and a display unit 166.

Still in this first embodiment of the invention, the processing unit 164is an air data computer, which is well known to one versed in the art,while the display unit 166 is an airspeed display on an electronicFlight Instrumentation System (EFIS), a multifunction Display (MFD), ora Head-Up Display (HUD), all of which are well known to one versed inthe art.

The processing unit 164 receives a selected display algorithm signalprovided by the user interface 160 and a measured speed signal providedby the speed measuring device 168.

The processing unit 164 provides a speed display signal to the displayunit 166.

Now referring to FIG. 14, there is shown how the electronic non-linearaircraft speed display 162 operates in the preferred embodiment of theinvention.

According to step 180, a display algorithm is selected using the userinterface 160. The selected display algorithm signal is provided by theuser interface 160 to the processing unit 164. In one embodiment, thedisplay algorithm is selected by the pilot of the aircraft while inanother embodiment of the invention, the display algorithm is selectedby the air data computer or the like.

According to step 182, a speed signal is measured using the speedmeasuring device 168 which provides the measured speed signal to theprocessing unit 164.

According to step 184, a speed display signal, comprising a speed tapeis provided on the display unit 166. The speed tape is provided by firstdetermining the speed display signal using the measured speed signal andthe selected display algorithm signal and providing the created speeddisplay signal to the display unit 166.

Now referring to FIG. 15, there is shown an example of a speed tape 190provided on an electronic non-linear aircraft dynamic parameter display.

The speed tape 190 comprises a dynamic non-linear speed scale 192, acorresponding non-linear speed value scale 194, a pointer 212 and anadjacent vertical bar 214.

Preferably, the dynamic non-linear speed scale 192 and the correspondingnon-linear speed value scale 154 are displayed vertically.

The dynamic non-linear speed scale 192 comprises a speed scale that isprovided between a first speed scale end 196 and a second speed scaleend 198

The corresponding non-linear speed value scale 194 comprises a pluralityof corresponding speed values and is provided between a first speedvalue 200 corresponding to the first speed scale end 196 and a secondspeed value 210 corresponding to the second speed scale end 210.

The pointer 212 is located substantially in the middle of the dynamicnon-linear speed scale 192. The pointer 212 comprises an indication ofthe measured speed signal.

The adjacent vertical bar 214 is located adjacent to the correspondingnon-linear speed value scale 194. Alternatively, the adjacent verticalbar 214 is located adjacent to the dynamic non-linear speed scale 192.

The adjacent vertical bar 214 comprises a variable end 216 which isadjacent to a corresponding future speed value 219. The adjacentvertical bar 214 therefore provides an indication of a future speedvalue if a current variation of the speed is maintained during apredetermined amount of time. In a preferred embodiment, thepredetermined amount of time is 10 sec.

The skilled addressee will appreciate that the corresponding futurespeed value 218 can easily be seen by the pilot of the aircraft lookingat the variable end 216.

It will be appreciated that the dynamic non-linear speed scale 192 isconstantly adapted according to the selected display algorithm signal.In one embodiment, the selected display algorithm signal is anexponential factor, in another embodiment of the invention, the selecteddisplay algorithm signal is a logarithmic factor; in another alternativeembodiment, the selected display algorithm signal is a geometric factor.

In fact, the selected algorithm is set so that the highest resolution isobserved immediately adjacent to the measured speed signal.

Furthermore, it will be appreciated that while a first part of thedynamic non-linear speed scale 192 is adapted according to a firstselected display algorithm signal, a second part of the dynamicnon-linear speed scale 192 may be adapted according to a second selecteddisplay algorithm signal.

In one embodiment, the first speed value 200 corresponding to the firstspeed scale end 196 and the second speed value 210 corresponding to thesecond speed scale end 198 are provided by the user interface 160 whilein the preferred embodiment, the first speed value 200 and the secondspeed value 210 are automatically selected by the air data computer. Itwill be appreciated that the first speed value 200 and the second speedvalue 210 may be selected according to the design of the aircraft.

In this example, the measured speed signal is 205 kts.

It will be appreciated that alternatively, the speed tape 190 comprisesan indication of characteristic speeds of the aircraft such as Vfe, VNe,Vg, Vl, Vr, etc.

Furthermore speed zones such as the “yellow arc”, the “green arc” andthe “white arc” may be added on the speed tape 190. The skilledaddressee will appreciate that the “white arc” 191 is shown on the speedtape 190 disclosed in FIG. 15.

It will be appreciated by the one skilled in the art that the embodimentenables the scale of the dynamic non-linear speed scale 192 to bemaximum in the vicinity of the measured speed signal.

Furthermore, the corresponding first speed value 200 and thecorresponding second speed value 210 are always displayed on the speedtape 190.

Moreover, as the aircraft approaches low or high airspeed, where mostlimitations are encountered, the dynamic non-linear speed scale 192ensures good legibility in these critical regimes.

As per the embodiment where the dynamic parameter is altitude, it willbe appreciated that the adjacent vertical bar 214 is of great advantageto show very high rate of change without exceeding available display.

While prior art trend vectors may be “pegged”, the embodiment disclosedtherein overcome such shortcoming which is of great advantage in thecase of military jets.

While it has been disclosed the dynamic parameter may be one of speedand altitude, the skilled addressee will appreciate that the dynamicparameter may alternatively be one of rotations per minutes (RPM), oilpressure, oil temperature, fuel flow, tachometer, remaining fuel or thelike.

The embodiments of the invention described above are intended to beexemplary only. The scope of the invention is therefore intended to belimited solely by the scope of the appended claims.

1. An apparatus for displaying a dynamic parameter, said apparatuscomprising: a processing unit receiving a selected display algorithmsignal and a reading of said dynamic parameter, said processing unitdetermining a display signal; and a display unit receiving said displaysignal and displaying a scale having scale ends, said scale changingdynamically and non-linearly in accordance with the selected displayalgorithm together with a minimum dynamic parameter value and a maximumdynamic parameter value, said display unit further displaying a pointerpointing to said scale in accordance with said reading of said dynamicparameter, such that said selected display algorithm constantly andexactly fits said reading, and the minimum and maximum dynamic parametervalues to said scale, thereby emphasizing a range of said reading ofsaid dynamic parameter while keeping said minimum and said maximumdynamic parameter values constantly and in view at respective scaleends.
 2. The apparatus as claimed in claim 1, further wherein said scalecomprises a vertical portion displayed vertically by said display unit.3. The apparatus as claimed in claim 2, wherein said dynamic parametercomprises the speed of a moving vessel.
 4. The apparatus as claimed inclaim 3, wherein said display unit displays said pointer with said speedof said moving vessel.
 5. The apparatus as claimed in claim 4, whereinsaid scale, displayed by said display unit, is extended between a lowspeed value and a high speed value, further wherein a plurality ofcorresponding speed values are displayed adjacently to said scale bysaid display unit.
 6. The apparatus as claimed in claim 3, furthercomprising a user interface providing said selected display algorithmsignal.
 7. The apparatus as claimed in claim 4, wherein said displayunit further displays an adjacent bar to said scale, said adjacent barcomprising a first end corresponding to said speed of the moving vesseland a variable end corresponding, on said scale, to a future speed to bereached by said moving vessel if a current variation of said speed ismaintained during a predetermined amount of time.
 8. The apparatus asclaimed in claim 7, wherein said display unit further displays a valueindicative of said variation of said speed.
 9. The apparatus as claimedin claim 7, wherein said predetermined amount of time is 10 seconds. 10.The apparatus as claimed in claim 1, wherein said scale, displayed bysaid display unit, is extended between a low dynamic parameter value anda high dynamic parameter value, further wherein a plurality ofcorresponding dynamic parameter values are displayed adjacently to saidscale by display unit.
 11. A method for displaying a dynamic parameter,said method comprising: providing a reading of said dynamic parameter;generating a scale having scale ends, said scale changing dynamicallyand non-linearly using said provided reading of said dynamic parameterand a selected display algorithm signal together with a minimum dynamicparameter value and a maximum dynamic parameter value, and a pointerpointing to said scale in accordance with said reading of said dynamicparameter; and displaying said scale, said minimum dynamic parametervalue and said maximum dynamic parameter value, such that said selecteddisplay algorithm constantly and exactly fits said reading, and theminimum and maximum dynamic parameter values to said scale, therebyemphasizing a range of said reading of said dynamic parameter whilekeeping said minimum and said maximum dynamic parameter values constantand in view at respective scale ends.
 12. The method as claimed in claim11, further comprising generating a plurality of corresponding dynamicparameter values, corresponding to said scale, further comprisingdisplaying said plurality of corresponding dynamic parameter valuesadjacently to said scale.
 13. The method as claimed in claim 11, furthercomprising selecting said selected display algorithm signal from aplurality of non-linear display algorithms.
 14. The method as claimed inclaim 13, wherein said plurality of non-linear display algorithmscomprise a geometric-based algorithm, an exponential-based algorithm, alogarithm-based algorithm or the like.
 15. The method as claimed inclaim 11, wherein said generating of said scale is performed using saidprovided reading of said dynamic parameter and more than one selecteddisplay algorithm signal, each of the more than one selected displayalgorithm signal being used for generating a corresponding part of saidscale.
 16. The method as claimed in claim 11, further comprisinggenerating an adjacent bar, said adjacent bar comprising a first endcorresponding to said dynamic parameter and a variable end correspondingto a future dynamic parameter value, if a current variation of saiddynamic parameter is maintained during a predetermined amount of time,further comprising displaying said adjacent bar adjacently to saidscale.
 17. The method as claimed in claim 16, wherein said displaying ofsaid adjacent bar further comprises displaying a value of said currentvariation of said dynamic parameter.
 18. The method as claimed in claim11, wherein said dynamic parameter comprises at least one of altitude,speed, rotations per minutes (RPM), oil pressure, oil temperature,engine temperature, fuel flow, tachometer and remaining fuel.
 19. Anapparatus for displaying a dynamic parameter, said apparatus comprising:a display unit receiving a display signal and displaying a scale thatchanges dynamically and non-linearly in accordance with a selecteddisplay algorithm, said scale being constantly adapted as a function ofa value of the dynamic parameter being displayed and upper and lowerboundaries of a display area of the display unit, said display unitfurther displaying a pointer pointing to said scale in accordance with areading of said dynamic parameter, thereby emphasizing a range of saidreading of said dynamic parameter.
 20. The apparatus as claimed in claim19, wherein said scale, displayed by said display unit, is extendedbetween a low dynamic parameter value and a high dynamic parameter valuefurther wherein a plurality of corresponding dynamic parameter valuesare displayed adjacently to said scale by said display unit.